That would include the computer and a client for peer to peer like Skype and other video conferencing applications. The meeting rooms with codecs integrated or not will have different requirements.
Wear A Headset
In order to address any audio feedback and the requirement for echo cancellation, these are a must plus you'll enjoy better audio quality. Headsets should be of the USB variety and where possible stay away from analog type connections and the cost around $40 to $60 dollars.
Aside from the audio issues being addressed it also takes care of privacy concerns.
